Radio condenser adjustment



Aug. 3l, 1926.

' J. L. NILSON El' AL RADIO CONDENSER ADJUSTMENT Filed Oct. 1. 1924 arrangement of parts, hereinafter described Patented Aug. 31, 1926.

, UNITED STATE-.sf PATENT oFFiCE .'IoHN L. NILsoN AND JOHN r. PRINCE, or CHICAGO, ILLINOIS.

m coNDEN'sEaAnJUsrMENr.

Applicationled October 1,

-the present improvement is the provision,'

in a compact, or space-saving, arrangement for changing the relative capacity of a plurality of condensers in, a set by making a part of the stators, as well as the. rotors, adjustablymovable, and our invention conslsts in the novel construction, combination and in detail, illustrated ins the accompanying drawing and more particularly pointed out in the appended claims.

In the accompanying drawing-- Figure 1 is a'planwiew of a set of three condensers together with a broken away ,portion of the base-board and `dial panel,

the blades of thecondensers being shown diaorammatically.

figure 2 is anenlarged side view in elevation of yone of the identical condensers,

p taken substantially on the line 2-2 of Fig-` ure 1,with) the upperportion of the panel` broken away. I Figure 3 is an enlarged section taken substantially on theline 3-3 of Figure 2, show-- ing the eccentric or-camjby means of which vthe two end 'stators ofthe set are adjusted on the axis of the condenserV shaft.

KIn the several views 2'represents the baseboard,or part over which the eenden-sers are mounted, and. 3 represents the yusual panel on the face of which is or are placed thedial or dials 15. The condensers, including all the parts of each, are indicated as 4, 5 and 6, respectively,kthe middle one- -having its stator portion fixed ,in the usual manner, while the two end condensers have their stators as well as their rotors mountedv for rotary adjusting movement. Each of these condensers is represented `in Figures l, 2 and 3 as having triangular frame-ends 7 and 8, between which are the l rotor plates 9 and -stator'plates 10 shown da'grammatically in Figure 1. The respective rotors are secured to, or keyed to, the

usual rotary shaft or spindle-11+, which.

' parallels the panel, while the stator blades` are secured to suitable .cross-pieces 12 andv A13 (Figure 1) between the sides or ends L7 'and 8. In Figure 1 the shaft 11, to which all thefrotors are ke ed, is rotated by a finger knob 14'ona "al 15..., The'kuob14` is eyed-to a shaft 16.0n` the innerend of Awhic is keyed "a bevel gear 1 8 adyacent tof 1924. serial No. 746,927.l

a bearing post 17 for the shaft' 16. The` gear 18 meshes with a similar gear 19 that is keyed to the shaft 11,-the-ends of .which are mounted on bearingsl 20 and 21. In 00 order to provide for the rotary movement of the stators indicatedby dotted lines in Figure 2, the condensers-are elevated by the shaft 11, the stator of'the condenser 5, or the ends 7 and 8 thereof, being provided 95". with a separatebase-board 22 the position of which relative to the middle condenser being indicated by dotted lines in Figure 2.

t, The stator, or condenser frame," of each of thecondensers 4 and 6 is rotatably sup# 70 ported by the shaft 11, and is adjustably 'held stationary by the mechanism shown 23 that yis eccentrically keyed to a lshaft 24 mounted in the bracket 25, the represented b 'panel 3 and on a bearingybearing in the panel being, a bore 26. On the cam y23 is ak ring or j trap 27 from which depends -80 ya lug 28 through which is a bore 29 to receive a stud Ior Ibolt projecting from the youter side of the end orl side frame-piece 7 which projection may be 'an extension of the usual frame crossrods-30-having thereon 85 the nuts 31. To the outer end of the shaft 24 is secured a turning knob, or kfinger-piece 32 secured as by a vpin 33. These khobs, like the knob 14, may ben rovided with suitable indicating dials suc f as 15. The ,99" mechanism for, rotating the latter in the usual and various ways, not forming a part of the present improvement, is not shown'.

The customary adjustment of the rotors through the medium of the knob 14 to vary 95 the capacity of the Vcondensers, may, by the rotary adjustment of one\or moreof the stators inthe manner herein shown, be thus minutely and accurately corrected, 'either plus or minus by manipulation of one orqoo/ more knobs 32 which vcontrol the stator positions. f

The common tunedradiol frequency receiver, whether under conditions where-in it becomes a neutrodyne, or a simple` selfwbalancing circuit, Inakes use of three tuned circuits, each consisting of coil or inductance and condenser or capacity. This condenser is the only variable element. The nh three tuned circults require three variable' condensensfwith three dials,` according to f the general. practice. The frequency to l' which each tuned circuit responds is, disregarding constants, directly proportional to the product of inductance and capacity, whose values are very small while their frequencies are very large or high. Hence an infinitesimal change in either inductance or capacity, or in both, will make a very large change in the frequency. Changes which are extremely minute in themselves will be reflected in great frequency changes,l and these minute changes may be caused by the deposit of dust in condensers, or in changes of temperature or humidity in either of the three circuits independently of the others.

' In the present improvement such changes may be compensated for by a very slight angular movement, or rotation, of the usually fixed portion of the condenser, or stator. 4

In the early usta es of this art the problem of'providing mec anisms which would operate within a minimum of space, was not. present to any appreciable extent. But as the art progresses the avoidance of the large spread of parts and the simplification of mechanisms and arrangements thereof is of growing importance. In the present improvement by supporting the shaft 11 on the two bearing standards 20 and 21 at the outer en'ds of the battery have adapted our invention to existing and approved form of condensers and the cam arrangement for moving individual stators, unlike the more or less complex and spread out mechanisms for the same purpose (which are now wholly unavailable for comercial purposes) invented in the early stages of the art, call for no space increases in existing receiving sets.

Ve claim as our invention.

1. In combination, a panel a plurality of condensers, a single shaft for same paralleling said panel, turning knobs with short shafts thereon which have their inner ends adjacent to rotatably mounted stator frames,

the stator frames, and stator-rotating means between said inner ends and stators.

`2. In combination, a plurality of condensers on a single shaft, rotatably mounted condenser stat'ors, a turning knob with a short shaft thereon for rotating individual stators spearately, and cam-members on said short shaft and individual stator, respectively, for adjustably rotating the individual stator.

In testimony whereof we have hereunto 55 signed our names. f

- JOHN L. NILSON. JOHN F. PRINCE.

of oondensers we a0 

